Mitsubishi Electric MELSEC iQ-F FX5 - Page 650

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35 CPU MODULE BUILT-IN ANALOG FUNCTION
35.6 Function (PID Control Via Parameter)
Control output cycle setting function
The control output cycle is a cycle of on/off signals being output from the control output to operate a control device such as a
heater and cooler.
Based on the output value calculated by PID control when the control output cycle starts, on signals are output from the
control output. After that, until the control output cycle elapses, the output from the control output is turned off.
When the PID control execution command is turned off, PID control stops. Therefore, the output from the control output is
turned off regardless of the output status.
■The control output cycle and the sampling time cycle match.
When the control output cycle and the sampling time cycle match, the control output is controlled by using the output value
calculated by PID control that is executed at the timing at which the control output cycle time elapses.
■The control output cycle and the sampling time cycle do not match
When the control output cycle and the sampling time cycle do not match, the control output is controlled at the timing of the
control output cycle. The output value (MV) used at that time is as follows.
• For the timing applicable when the control output cycle and the sampling time cycle match, in the same way as previously
mentioned, use the output value (MV) calculated by PID control that is executed at that timing.
• For the timing applicable when the control output cycle and the sampling time cycle do not match, use the output value
(MV) calculated by PID control that has been executed immediately before the said timing.
ON
OFF
MV=60.0%
MV=40.0% MV=40.0%
MV=45.0% MV=40.0%
Measured value (PV)
Target value
(SV)
Sampling time
(250ms)
Time
Output value (MV)
= 60.0%
Output value (MV)
= 40.0%
Control output
Control output cycle (1s)
Control output cycle (1s)
ON
OFF
MV=60.0%
MV=40.0%
MV=45.0%
MV=40.0%
MV=40.0%
Measured value (PV)
Target value
(SV)
Sampling time
(300ms)
Time
Output value (MV)
= 60.0%
Output value (MV)
= 45.0%
Control output
Control output cycle (1s) Control output cycle (1s)